FIELD: chemistry.
SUBSTANCE: present invention relates to ester compositions which include molten-phase derived polyethylene terephthalate. Described is an ester composition for packaging, which includes: molten phase-derived polyethylene terephthalate, with fragments of terephthalic acid and a monomer which contains two or more condensed aromatic rings, in amount of about 0.5 mol % to 2.5 mol % with respect to the total amount of dicarboxylic acid residues in the molten phase-derived polyethylene terephthalate, making up 100 mol %; and titanium alkoxide, where the titanium alkoxide is present in amount of 30-100 ppm of titanium atoms with respect to the total weight of the ester composition, where the polyester composition is in the form of transparent granules which do not contain TiO2, antimony or germanium, and where the polyester composition contains molten phase-derived polyethylene terephthalate, with inherent viscosity (I.V.) of at least 0.75 dl/g. Also described is a polyester composition for packaging, which includes: molten phase-derived polyethylene terephthalate, with fragments of 2,6-naphthalene dicarboxylic acid, in amount of about 0.5 mol % to 2.5 mol % with respect to the total amount of dicarboxylic acid residues in the molten phase-derived polyethylene terephthalate, making up 100 mol %; and titanium alkoxide, which is present in amount of 5-60 ppm of titanium atoms with respect to the total weight of the polyester composition, where the polyester composition is in the form of transparent granules which do not contain TiO2, antimony or germanium, and where the polyester composition contains molten phase-derived polyethylene terephthalate, with inherent viscosity (I.V.) of at least 0.75 dl/g. Described is a method of producing a molten phase-derived polyethylene terephthalate composition, which includes: preparing a mixture of monomers containing ethylene glycol, at least one acid selected from terephthalic acid, and a monomer with two or more condensed aromatic rings, where the monomer with two or more condensed aromatic rings is present in amount of about 0.5-2.5 mol %, with respect to the total amount of dicarboxylic acid residues in the mixture, making up 100 mol %; esterifying the mixture of monomers in the absence of a catalyst to obtain a mixture of oligomers at temperature of 245°C and pressure of up to 40 psig; and reacting the mixture of oligomers in the presence of titanium alkoxide and in the absence of TiO2 to obtain molten phase-derived polyethylene terephthalate, where the obtained molten phase-derived polyethylene terephthalate has inherent viscosity (I.V.) achieved in a molten phase of at least 0.76 dl/g; and then moulding granules of molten phase-derived polyethylene terephthalate to obtain transparent granules; where the molten phase-derived polyethylene terephthalate does not contain germanium or antimony and where titanium alkoxide is present in amount of 30-100 ppm of titanium atoms with respect to the total weight of the obtained polyester composition.
EFFECT: obtaining an ester composition for packaging, which includes molten phase-derived polyethylene terephthalate, which exhibits thermal oxidative stability.
11 cl, 4 tbl, 7 ex
